There's scant science and much nonsense in the debate over Propositon 37, would require some food sold in California and produced via genetic engineering to be labeled as such.

Sorry, that won't do. Mercola isn't just any backer of Proposition 37; he's the biggest donor, and one who has built his business around some of the scare claims inherent in an anti-genetic engineering initiative. Moreover, he didn't just write a check — he was solicited to contribute in February by Doug Linney, then the initiative's campaign manager, who could not have been unaware of Mercola's history.

The campaign's founding organizer, Ruskin says, is Pamm Larry, 56, a Chico business owner and organic farmer who says she began traveling the state earlier this year on her own to drum up interest in a ballot measure.

Larry has appeared in a promotional video with Mercola and clearly has been deeply influenced by him. "I really admire the man and very much admire his integrity," she says. She has bought into Mercola's depiction of the FDA as a wickedly ineffective bully — she praises him for "standing up" to the agency over mammograms — but her grasp of the facts is poor.

"The FDA approved thalidomide!" she informed me during a brief interview, referring to the morning-sickness drug that produced an epidemic of birth defects in the 1950s and 1960s. Well, no. The FDA banned thalidomide, sparing the U.S. from the worst of the disaster. Meanwhile, she seems to think Mercola's interest in Proposition 37 is entirely altruistic, despite his multimillion-dollar "natural" products empire.

On the other side of the ballot campaign is, big surprise, the food processing and agribusiness industries. Biggest donors to "No on 37" (as of Aug. 15): Monsanto ($4.2 million), DuPont ($4 million) and PepsiCo ($1.7 million).

They contend, among other things, that the measure would increase California farmers' costs by $1.2 billion a year. Their source? A study for which they paid two UC Davis agriculture professors, Julian M. Alston and Daniel A. Sumner, at least $30,000. Their paper acknowledges that the direct implications of the initiative for California agriculture "are very difficult to assess," a disclaimer you won't find in the No on 37 advertising.

The study assumes that food producers will respond to Proposition 37 by removing genetically engineered ingredients to avoid the labeling. The authors don't devote much attention to the possibility that producers will respond to the labeling mandate by simply relabeling, which seems the easiest course since as much as 70% of the food in our groceries contains some genetically engineered ingredient.

Sumner told me the main resistance to labeled foods may come from supermarkets — because they fear not customer backlash, but street activism. "If I'm Safeway, I could figure that 95% of my customers may not care … but what they don't want is somebody dressed in a Frankenstein suit marching in front of the store." Is that a plausible concern? Here's betting that the Frankenstein regalia will get pretty old pretty quickly for anyone inclined to marching in front of his local Vons in the heat or rain.

Another claim is that Proposition 37 will generate "shakedown" lawsuits against mom-and-pop groceries because the measure allows private attorneys to sue to enforce the law. The No campaign cites Proposition 65 of 1986, which mandated those now-familiar warnings about toxic chemicals on buildings and workplaces and was drafted by James Wheaton, an environmental attorney who also drafted Proposition 37. "The real threat is not against giant companies but small businesses," says the No campaign's legal advisor, Tom Hiltachk.

Yet there's a difference between the two measures. Proposition 65 granted private attorneys a share of fines and penalties exacted from violators, making it more of a bounty system. Proposition 37 doesn't — private attorneys can sue only to obtain injunctions, not penalties, Wheaton says. They can get their legal fees paid if they prevail, but a big score plainly doesn't exist.

The measure's opponents say small businesses will still be vulnerable to petty legal harassment, but Wheaton contends what the opponents really desire is to limit enforcement to the attorney general or district attorneys, who are sure to treat it as a low priority. "They want no enforcement," he says.

Anyway, Proposition 37 is aimed chiefly at food processors; the No campaign's professed concerns notwithstanding, the entities it's looking out for aren't mom-and-pop fruit stands but Gog and Magog-scale companies like Monsanto and DuPont. Those firms' interest lies in quelling public activism against genetically modified foods, and the best tool for that is to limit the flow of information.

The public's interest, for that matter, lies in a reasoned, informed debate about whether to label, what to label and how to label. In the next six weeks that debate will be waged in 15- and 30-second television spots, and that's no way to make law.